Playing through this on the 360 right now. EXTREMELY impressed with the game world and the general sense of atmosphere. Mafia II might be the most immersive game I've ever played.
The first time you're in Empire Bay, with Joe driving you around, I was in awe. The lightly falling snow, the 1940s music on the radio, the Brooklyn Bridge... amazing. Little details like the snow actually collecting in the center of the road, with ruts where car tires have been driving through just make the world seem so real.
Driving around in that winter environment in a sharp suit with "Baby, It's Cold Outside" on the radio, seeing all the woman pedestrians carrying umbrellas & men wearing hats, and snow collecting on the back bumber of the car... amazing. It IS the 1940s.
I was so immersed in the environment, the storytelling, and the characters, that the first time Joe lets you drive but STRONGLY warns you not to scratch up his car, I was literally afraid to drive fast. :lol I don't think anything like that has happened to me in a game before. I didn't want to bump any other cars not because I would have to restart the mission or anything like that, but because I was worried about upsetting my fictional polygonal friend. It's insane.
The game itself is so-so, and I eventually snapped out of my immersive reverie and played the game like a normal gamer (driving on the sidewalk, etc.) But those first few hours were pure magic. The game is worth playing just to experience the atmosphere alone.